Final answer:
Fabric is considered unairworthy when it has deteriorated to approximately 60% of its original strength.
Step-by-step explanation:
In aviation, fabric is often used in the construction of aircraft components, particularly in older aircraft or certain types of light aircraft. The determination of when fabric becomes unairworthy is crucial for ensuring the safety and reliability of the aircraft. Generally, fabric strength is measured by tensile strength, and the threshold for considering fabric as unairworthy is around 60% of its original strength.
The degradation of fabric can result from various factors, including exposure to environmental elements such as UV radiation, humidity, and mechanical wear. Over time, these factors can cause the fabric to lose its tensile strength, which is the amount of stress a material can withstand while being stretched or pulled.
When fabric reaches approximately 60% of its original tensile strength, it is considered to be in a state of significant deterioration, compromising its structural integrity and making it unsuitable for aviation use. Regular inspections and maintenance are essential to monitor the condition of fabric components and replace them when necessary, ensuring the continued airworthiness of the aircraft.
In summary, the 60% threshold for fabric strength is a critical criterion in determining when fabric becomes unairworthy. This standard helps maintain the safety and reliability of aircraft by preventing the operation of aircraft with compromised fabric components that could pose a risk during flight.